Kev siv DTV (digital TV) thiab HDTV (txhais tau TV) tshaj tawm hauv xyoo 2009 thaum lub sijhawm hloov DTV hloov pauv li cas cov ntsiab lus hauv TV tau tshaj tawm thiab nkag mus los ntawm cov neeg siv khoom hauv Teb Chaws Asmeskas Nws kuj tau nce mus rau cov ntawv sau ua kua zaub. ntawm cov nqe lus. Ntawm cov nqe lus no yog DTV thiab HDTV.
Txhua qhov kev tshaj tawm HDTV yog DTV, tab sis tsis yog tag nrho DTV tshaj tawm yog HDTV
Tib lub bandwidth faib rau DTV tshaj tawm tuaj yeem muab ntau yam kev daws teeb meem digital channel (SDTV) thiab lwm yam kev pabcuam lossis xa ib lossis ob lub teeb liab HDTV tag nrho.
Pawg Neeg Saib Xyuas Kev Tshaj Lij Tshaj Lij Tshaj Lij Tshaj Lij Tshaj Lij (ATSC) tau ua 18 cov qauv daws teeb meem muaj rau kev tshaj tawm digital TV. Tag nrho cov built-in thiab sab nraud digital TV tuners yuav tsum txiav txim siab tag nrho 18 hom. Txawm li cas los xij, kev siv DTV tshaj tawm, tau nqis los rau peb qhov kev daws teeb meem: 480p, 720p, thiab 1080i.
480p (SDTV)
Qhov kev daws teeb meem 480p ntawm SDTV (tus qauv txhais lus TV) zoo ib yam li analog TV tshaj tawm tab sis kis tau los ntawm digitally (DTV). Cov duab no yog ua los ntawm 480 kab lossis pixel kab ntawm kev daws teeb meem scanned mus, tsis yog nyob rau hauv lwm qhov chaw xws li hauv analog TV kis.
Qhov no muab cov duab zoo, tshwj xeeb tshaj yog ntawm cov ntxaij vab tshaus me me 19-nti rau 29-nti. Nws yog ntau zaj duab xis-zoo li tus qauv cable lossis txheem DVD tso zis. Nws kuj tseem muab ib nrab ntawm qhov muaj peev xwm video zoo ntawm daim duab HDTV. Qhov no txhais tau hais tias nws cov txiaj ntsig tau qis dua ntawm cov npo loj loj (TVs nrog lub vijtsam loj 32 ntiv tes thiab siab dua).
Txawm hais tias 480p yog ib feem ntawm DTV tshaj tawm cov qauv pom zoo, nws tsis yog HDTV. Nws tau suav nrog muab cov xov xwm tshaj tawm txoj kev xaiv los muab ntau txoj hauv kev ntawm kev ua haujlwm thiab kev pabcuam hauv tib lub channel bandwidth faib ua ib lub teeb liab HDTV. Nws zoo ib yam li qhov koj yuav pom hauv lub teeb liab analog TV, nrog kev nce me ntsis hauv cov duab zoo.
720p
Lwm hom DTV, 720p (720 kab ntawm kev daws teeb meem tau tshuaj ntsuam zuj zus), kuj suav tias yog HDTV.
ABC thiab Fox siv 720p raws li lawv cov qauv tshaj tawm HDTV. Qhov kev daws teeb meem no muab cov duab du, zoo li zaj duab xis vim nws qhov kev ua tiav scan ua tiav. Ntxiv rau, cov duab nthuav dav tsawg kawg yog 30 feem pua ntau dua li 480p. Nws muab cov duab hloov kho kom haum rau nruab nrab (32-nti rau 39-nti) thiab cov ntxaij vab tshaus loj. Tsis tas li ntawd, txawm tias 720p yog suav tias yog qhov txhais tau hais, nws siv tsawg dua bandwidth tshaj 1080i.
1080i
Qhov feem ntau siv HDTV hom rau tshaj tawm TV tshaj tawm huab cua yog 1080i (1,080 kab ntawm kev daws teeb meem scanned hauv lwm qhov chaw ntawm 540 kab txhua). PBS, NBC, CBS, thiab CW (nrog rau satellite programmers TNT, Showtime, HBO, thiab lwm yam kev pab them nqi) siv nws raws li lawv cov qauv tshaj tawm HDTV.
Txawm hais tias tseem muaj kev sib cav txog seb 1080i zoo dua li 720p hauv qhov tseeb ntawm cov neeg saib, 1080i technically muab cov duab ntxaws tshaj plaws ntawm 18 pom zoo DTV tshaj tawm cov qauv. Qhov pom kev cuam tshuam ntawm 1080i, txawm li cas los xij, poob ntawm lub vijtsam me dua 32 ntiv tes.
Ntawm qee qhov ntxiv 1080i qhov tseeb:
- 1080i siv qhov bandwidth tshaj plaws ntawm tag nrho cov ntawv tshaj tawm DTV.
- 1080i yog lub teeb liab interlaced. Cov duab teeb liab yog tsim los ntawm cov kab sib hloov lossis pixel kab es tsis txhob ua cov kab los yog kab raws li hauv 480p thiab 720p.
- 1080i tsis tuaj yeem tso tawm hauv nws daim ntawv tiag tiag ntawm LCD, OLED, ntshav, lossis DLP TV. Txhawm rau tso tawm 1080i cov cim qhia, cov hom teeb tsa hloov pauv 1080i teeb liab mus rau 720p lossis 1080p.
Yog tias koj muaj 1080p LCD, OLED, plasma, lossis DLP TV, nws deinterlaces lub teeb liab 1080i thiab qhia nws ua 1080p duab. Yog tias ua tau zoo, cov txheej txheem no tshem tawm tag nrho cov kab pom pom los ntawm cov duab interlaced 1080i, ua rau cov npoo du. Los ntawm tib lub cim, yog tias koj muaj 720p HDTV, koj lub TV deinterlaces thiab downscales 1080i duab rau 720p rau kev tshuaj ntsuam.
Dab tsi txog 1080p?
Txawm hais tias 1080p yog siv rau Blu-duab tshav, cable, thiab internet streaming, nws tsis yog siv nyob rau hauv tshaj tawm hauv TV. Yog vim li cas yog tias, thaum DTV tshaj tawm cov qauv tau pom zoo, 1080p tsis tau pib nrog.
Ntau dua: 4K thiab 8K
Txawm hais tias kev tshaj tawm DTV yog tus qauv tam sim no, cov qauv tom ntej no suav nrog 4K daws teeb meem thiab, nyob deb ntawm txoj kev, peb yuav pom 8K.
Thaum pib, txoj haujlwm kev lag luam yog qhov kev tshaj tawm 4K thiab 8K kev daws teeb meem saum huab cua yuav ua tsis tau vim yog qhov xav tau ntawm bandwidth loj. Kev sim tsis tu ncua, txawm li cas los xij, tau ua rau kev ua kom zoo nkauj video compression thiab lwm yam thev naus laus zis uas ua haujlwm nrog kev nce qis hauv bandwidth. Cov qauv tshiab uas yuav suav nrog 4K raug xa mus rau ATSC 3.0 lossis NextGen TV tshaj tawm.
Raws li TV chaw nres tsheb ua cov cuab yeej tsim nyog thiab kev hloov pauv hloov pauv, thiab cov neeg tsim TV tau koom nrog cov tuners tshiab rau hauv TVs thiab ntsaws-hauv lub thawv teeb tsa, cov neeg siv khoom yuav nkag tau mus rau 4K TV kis tau tus mob. Txawm li cas los xij, tsis zoo li hnub nyuaj uas yuav tsum tau hloov pauv los ntawm analog mus rau digital / HDTV tshaj tawm, kev hloov mus rau 4K yuav qeeb thiab yog kev yeem raws li tam sim no.
Kev siv 4K TV tshaj tawm yog lag luam qis dua lwm txoj hauv kev nkag mus rau 4K cov ntsiab lus, xws li los ntawm kev pabcuam hauv internet, suav nrog Netflix thiab Vudu, nrog rau ntawm lub cev Ultra HD Blu-duab tshav Disc hom. DirecTV kuj tseem muaj kev txwv 4K satellite pub.
Lub caij no, txawm hais tias kev siv zog loj yog coj 4K rau kev tshaj tawm hauv TV, Nyiv tseem tab tom thawb ua ntej nrog nws 8K Super Hi-Vision TV tshaj tawm, uas suav nrog txog 22.2-channel audio.
Thaum 8K TV tshaj tawm yuav muaj nyob rau ntawm qhov dav, txawm li cas los xij, yog leej twg xav tau. 4K TV tshaj tawm thaum kawg pib tau txais kev sib tw thoob plaws hauv xyoo 2021, yog li ua kom lwm qhov dhia mus rau 8K yog zaum kawg kaum xyoo dhau los.
